Photo courtesy of Christopher L. Wood
First, according to an article by Marc Morrone in the Providence Journal (May 17, '15, Sec. H2), there is no way a bird can have any idea of the sex of a human, as we are just too far removed from their species on the evolutionary scale. That means that although you may think a parrot squawks at you because he is a male and you are a male threatening his space, it "just ain't so, Joe."
A bird may prefer the company of men to women and vice versa, but the choice is based on the bird's interpretation of human actions, voice, or appearance. Not whether it shares the same estrogen or testosterone. Sounds like a good plan for humans!
If you are searching for the sex of a bird, you needn't peek "down under." There is a test to determine that, and it's not the kind you think. Pluck a few feathers from its breast (male and female) and mail them to a laboratory. You will be charged a fee, but the lab can extract the DNA and within a few days answer your crushing question. An example of a lab is Research Associates Laboratory at vetdna.com. Wouldn't want to have two female birds in a cat fight in the cage as you sip your morning coffee, would you?
Photo courtesy of Dick Tipton
Photo courtesy of Gerrit Vyn
Here is an interesting fact about woodpeckers. Woodpeckers sing. Not with their throats, but by pecking on a piece of metal or anything that makes a ringing sound. This is again according to Marc Morrone, not me. The noise makes a sound that's bigger and stronger than other male woodpeckers, who use mere trees made of wood. The bigger the sound, the prettier the mate and the better the nesting area.
If you have a woodpecker that's disturbing you during mating season, you'd better determine first whether it's causing damage to the wooden frame of your home. If not, get on a ladder and cover the woodpecker's favorite pecking area with cloth secured by duct tape. Or Marc suggests taping a few children's pinwheels with long ribbons to the spot the woodpecker loves. As the wind blows, the pinwheel ribbons in the wind will chase him off. Either that, or they'll chase your neighbors off!